Sherlock writer and actor Mark Gatiss will return to his Braavosi roots on Game of Thrones season 5.

Fans of the BBC’s Sherlock and Doctor Who can look forward to seeing a familiar face return in the fifth season of HBO’s Game of Thrones.

According to Entertainment Weekly, Mark Gatiss will reprise his role as Tycho Nestoris when the epic fantasy series returns in 2015. Gatiss, who writes on both BBC series and plays the enigmatic Mycroft Holmes on Sherlock, originated the role in season 4, to a response of significant fannish glee.

Gatiss is said to be filming in Croatia next week, which means that while Tycho Nestoris may be seen in his native Braavos, it is also possible that he will play a role in the turbulent politics of King’s Landing.

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Though Gatiss’ role is a small one, his character’s impact is set up to be significant on future seasons of Game of Thrones. As a representative of the formidable Iron Bank of Braavos, Tycho Nestoris is instrumental in shifting the Bank’s Westerosi allegiance (and funding) from the ruling House Lannister to the then-destitute Stannis Baratheon. In providing King Robert’s brother with the money to hire and provide for troops, Nestoris may have changed the course of succession in the Seven Kingdoms.

Without a doubt, Nestoris’s actions inadvertently saved the Night’s Watch from violent annihilation. The gold provided by the Iron Bank financed Stannis’ attack on the wildlings at the conclusion of season 4, meaning that Jon Snow and his much-reduced Black Brothers will fight another day.

And also, they now have King Stannis (and his wife, and his Davos, and his magical mistress Melisandre) to take care of. So really, they just about break even.

Game of Thrones season 5 will return to HBO in Spring 2015.

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